Two weeks from Tuesday, Iowa voters will head out to almost 1,800 caucus sites to help select a Republican presidential nominee. It could be cold. It could also be snowing. And the campaigns know they'll have to work hard to make sure their supporters show up. Those get-out-the-vote efforts could make all the difference in a race that now appears to be up for grabs.

Drake University student Ben Levine is home right now in Minnesota for the holidays. But next week, he'll be back in Iowa joining an army of young volunteers who plan to spend their holiday break working for Ron Paul.

"We'll be doing a lot of ground campaigning, going door to door, talking to Iowa voters directly," Levine says. "We'll be doing a lot of phone calls, phone banking from the headquarters in Iowa to get the vote out, remind people who are staunch Ron Paul supporters to go out and vote."

Paul is the oldest of the candidates by far, but his campaign has generated strong interest among the youngest voters: students. The Texas congressman's opponents openly admit he has the most enthusiastic, if not the best, ground operation in the state — and that it could put him over the top on Jan. 3.

"I want things to change so desperately that I'm willing to go all-out and campaign for him. I think the enthusiasm really comes, because young people when they get behind something, they have a ton of energy," says Levine.

And that's what it takes — reminding supporters to not only show up and vote, but to get their friends out, too. All the campaigns have lists of potential backers whom they'll contact repeatedly in the days ahead.

"Obviously, we'd love your support at the caucus. ... But we also need folks to help at the caucus and to help us before the caucus," former Pennsylvania Sen. Rick Santorum told a group of potential supporters in Carroll, Iowa, last week.

Aides were there to pass around a signup sheet for precinct captains and postcards that people can send to their friends.

"Bumper stickers, yard signs, talk to your friends. I'd be happy to stick around a few minutes if you want to take pictures. Put them up on Facebook. Tweet. Talk to your friends. Network. Try to get them to come to the caucus for us," urged Santorum.

"Real estate professionals talk about the three most important factors being location, location and location. In electoral politics, the three most important factors are turnout, turnout and turnout," explains Dennis Goldford, politics professor at Drake.

Goldford says it's a little like a chain letter. You get some base support and then try to spread it from one person to the next. A good ground operation isn't sufficient to win, Goldford says, but it is necessary.

He notes that former House Speaker Newt Gingrich was in the lead and is now the target of aggressive attacks from his opponents. But he doesn't have much of a ground organization to help out.

Gingrich "didn't have the infrastructure in place to build on that initial enthusiasm for him. And so it's not there as a safety net when he starts to fall back," says Goldford.

Goldford says Mitt Romney has a better ground organization, but the former Massachusetts governor hasn't spent much time in the state.

And for getting out the vote in Iowa, it's also all about personalize, personalize, personalize.

Which is one reason that Minnesota Rep. Michele Bachmann is making 99 separate video appeals, one for each of the 99 Iowa counties she is currently scheduled to visit before the caucuses.

Bachmann's campaign manager, Keith Nahigian, says the messages will be used in caucus training videos. They'll go to supporters around the state, so they know exactly where and when to go vote.

"On the ground is where Iowa happens. If you're not on the ground, you're not going to win," says Nahigian.

Which is why Levine can't wait to get back on the ground to promote his favorite candidate. Caucus night also happens to be Levine's 20th birthday.

"I'm pretty excited, actually," Levine says. "I decided that the best birthday present I could get is for Paul to win in Iowa."

Copyright 2012 National Public Radio. To see more, visit http://www.npr.org/.

Transcript

ROBERT SIEGEL, HOST:

We just heard reference to the Iowa caucuses as a turnout exercise. And turnout is a big challenge. Two weeks from tonight in Iowa, it is likely to be cold. It could be snowing and the campaigns know that they'll have to work hard to make sure that their supporters show up.

As NPR's Pam Fessler explains, efforts to get out the vote in Iowa could make all the difference.

PAM FESSLER, BYLINE: Drake University student, Ben Levine is home right now in Minnesota for Christmas. But come December 27th, he'll be back in Iowa joining an army of young volunteers who plan to spend their holiday break working for Ron Paul.

BEN LEVINE: You know, going door-to-door, talking to Iowa voters directly. We'll be doing a lot of phone calls, phone banking, from the headquarters in Iowa to get the vote out, remind people who are staunch, you know, Ron Paul supporters to go out and vote.

FESSLER: Paul is the oldest of the candidates by far, but his campaign has generated strong interest among the youngest voters - students. The Texas congressman's opponents openly admit he has the most enthusiastic, if not the best, ground operation in the state and that it could put him over the top on January 3rd.

LEVINE: I want things to change so desperately that I'm willing to go all out and campaign for him. I think the enthusiasm really comes because young people, when they get behind something, they have a ton of energy.

FESSLER: And that's what it takes. Reminding supporters to not only show up and vote, but to get their friends out, too. All the campaigns have lists of potential backers who they'll contact repeatedly in the days ahead.

RICK SANTORUM: Obviously, we'd love your support at the caucus, but we also need folks to help us at the caucus and to help us before the caucus.

FESSLER: Former Pennsylvania Senator Rick Santorum is making his pitch to a group of potential supporters in Carroll, Iowa. Aides pass out a signup sheet for precinct captains and postcards that people can send to their friends.

SANTORUM: Bumper stickers, yard signs. And I'd be happy to stick around for a few minutes. If you want to take pictures, put them up on your Facebook, tweet, talk to your friends, network. Try to get them to come to the caucus for us.

DENNIS GOLDFORD: Where real estate professionals talk about the three most important factors being location, location and location. In electoral politics, the three most important factors are turnout, turnout and turnout.

FESSLER: Dennis Goldford is a politics professor at Drake University in Des Moines. Goldford says a good ground operation isn't sufficient to win, but it is necessary. He notes that former House Speaker, Newt Gingrich, who was in the lead, is now the target of aggressive attacks from opponents and he doesn't have much of a ground organization to help.

GOLDFORD: He didn't have the infrastructure in place to build on that initial enthusiasm for him, and so it's not there as a safety net when he starts to fall back.

Goldford said Mitt Romney's organization is better, but that the former Massachusetts governor hasn't spent much time in the state. And for getting out Iowa's voters, it's also about personalize, personalize, personalize.